After nearly 37 years in operation, Germany's oldest atomic reactor, in Obrigheim, was disconnected on Wednesday, Baden-Württemberg state officials said.

Energie Baden-Württemberg (EnBW) said the shutdown would cost some 500 million euros ($642 million). The three-phase shutdown process is expected to last until around 2020, the company said.

Two down... 17 to go?

Obrigheim nuclear plant

Obrigheim is the second reactor that was shut down as a result of national legislation agreed between the EnBW and the red-green coalition government in the summer of 2000. The first to close was E.ON's 672 mw Stade reactor, which was switched off in November 2003.

The 340 megawatt Obrigheim reactor will be prepared for final shut down over the course of the year. There are 17 other atomic reactors still active in Germany.

But despite the German energy policy, nuclear power is back in vogue elsewhere in Europe. Atomic reactors produce almost no greenhouse gas emissions, unlike coal and gas power stations.

Debated issue

The policy of phasing out nuclear energy is still subject to debate, however. Industry and political opposition want it to be reviewed but the government is standing firm by the 2000 decision.

The southern German state's environment minister, Tanja Gönner, told Reuters news agency she wants a discussion on the possible lengthening of running times of EnBW's remaining nuclear facilities in Baden-Württemberg.

Baden-Württemberg relies on nuclear energy for 55 percent of its electricity. Replacing lost local nuclear power with imported nuclear power from France or restarting idled coal plants does not make sense, especially if Germany wants to meet climate protection targets, Gönner said.